Chemical bonds (AQA GCSE Combined Science: Trilogy): Revision Note Exam code: 8464

Chemical bonds (AQA GCSE Combined Science: Trilogy): Revision Note

Exam code: 8464

Combining atoms

  • Atoms combine with other atoms through the movement of electrons, which could be considered as the “language of chemistry”

  • They do this in order to achieve a greater level of stability, which is reached when the atom obtains a full outer shell of electrons

  • There are three types of bonding studied at GCSE 

  • Ionic bonds:

    • Takes place when metals and non-metals react by transferring electrons

    • The atoms involved are oppositely charged particles (known as ions) in which electron transfer occurs

    • The opposite charges attract through electrostatic forces

  • Covalent bonds:

    • non-metal atoms share pairs of electrons between each other

  • Metallic bonds:

    • This type of bonding occurs in metals and metal alloys (mixtures of metals)

Examiner Tips and Tricks

Intermolecular forces are not chemical bonds. Electron transfer or sharing does not occur, and no new compounds are formed. Typically, intermolecular forces are around one-tenth the strength of a chemical bond.


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